Answer: 1.59 sec
Explanation:
The kinetic energy contained in the rotation of the cylinder is 1/2 m v^2
The kinetic energy of translation is also 1/2 m v^2
so the total energy is m v^2
The force applied is mg sin (theta)
= m x 9.8 x 1/2
= 4.9 m
Now equate
F x d = m v^2
4.9 m x 3.1 = m v^2
v^2 = 4.9 x 3.1
v = sqrt(4.9 x 3.1) = 3.9 m/s
Acceleration.
V^2 = 2 a s
4.9 x 3.1 = 2 x a x 3.1
4.9 = 2 a
a = 2.45 m/s^2
Time
T = v/a
= 3.9/2.45
= 1.59 sec
Answer:
2.5
Explanation:
The capacitance of a parallel-plate capacitor filled with dielectric is given by

where
k is the dielectric constant
is the capacitance of the capacitor without dielectric
In this problem,
is the capacitance of the capacitor in air
is the capacitance with the dielectric inserted
Solving the equation for k, we find

Answer:
It corresponds to 1mm-10 mm range.
Explanation:
- Electromagnetic waves (such as the millimeter-wave radiation) travel at the speed of light, which is 3*10⁸ m/s in free space.
- As in any wave, there exists a fixed relationship between speed, frequency and wavelength, as follows:

- Replacing v= c=3*10⁸ m/s, and the extreme values of f (which are givens), in (1) and solving for λ, we can get the free-space wavelengths that correspond to the 30-300 GHz range, as follows:


Answer:8540 kg-g/s
Explanation:
Given
mass of blue car 
velocity of blue car 
mass of the truck 
speed of truck 
After collision they stick and lock together
Let v be the velocity of combined system at angle \theta from vertical
Conserving momentum in east direction

------1
Conserving Momentum in Y direction

-------2
squaring and then adding 1 & 2 we get

v=10.95 m/s
initial momentum of car
The answer would be C. Lightning occurs when the negative charges from clouds attract towards the positive charges on the ground. These two charges attract and cause the spark of lightning. Hope this helps.